Method of manufacturing a gas burning artificial log from sol-gel compositions

Abstract

An active log 20 includes a body made of porous ceramic material. A channel is defined within the active log, within which is carried a gas tube 40. A gas supply line 60 provides gas to the gas tube 40. Gas exhausted from holes defined in the gas tube moves through the porous material from which the active log is constructed, cooling the active log by convection. Due to the slightly greater gas pressure within the active log, gas moves outwardly through the porous material, until it is exhausted from pores on the surface of the active log. Contact with the ambient atmosphere results in combustion. Because the combustion is generally uniformly distributed about the external surface of the active log, and because there is no unsightly external burner from which gas is exhausted, the appearance of the active log is a realistic approximation of the burning surface of a real log. One or more passive objects, such as logs or rocks, constructed of a similar porous ceramic material may be used to provide additional realism without the need to pipe gas to a number of gas tubes 40.

What is claimed is:  
     
       1. A method of making an active log, comprising: 
       (A) assembling a liquid part A, comprising:  
       (a) colloidal silica; and  
       (b) foaming agent;  
       (B) assembling a solid part B, comprising:  
       (a) anhydrous silicate powder;  
       (C) whipping the liquid part A while the solid part B is added, thereby forming a homogeneous whipped mixture, whereby the density of the whipped mixture is lowered by addition of air;  
       (D) placing the whipped mixture into a mold carrying a gas tube defining at least one hole and having a gas connection fitting; and  
       (E) curing and demolding the active log.  
     
     
       2. A method of making an active log of  claim 1 , wherein the whipped mixture additionally comprises: 
       (A) ceramic bulk fiber;  
       (B) glass needles; and  
       (C) a wetting agent.  
     
     
       3. A method of making an active log of  claim 2 , wherein the wetting agent is a fluorocarbon wetting agent. 
     
     
       4. A method of making an active log of  claim 1 , wherein the whipped mixture additionally comprises: 
       (A) microspheres with thin walls;  
       (B) microspheres with thick walls;  
       (C) light weight filler of foamed silica perlite; and  
       (D) light weight filler ultralight ceramic microspheres.  
     
     
       5. A method of making an active log, comprising: 
       (A) assembling a liquid part A, comprising:  
       (a) colloidal silica;  
       (b) ceramic bulk fiber;  
       (c) glass needles, 1-3%;  
       (d) fluorocarbon wetting agent; and  
       (e) foaming agent;  
       (B) assembling a solid part B, comprising:  
       (a) microspheres with thin walls;  
       (b) microspheres with thick walls;  
       (c) light weight filler of foamed silica perlite;  
       (d) light weight filler ultralight ceramic microspheres;  
       (e) anhydrous sodium silicate powder; and  
       (f) anyhdrous potassium silicate powder  
       (C) whipping the liquid part A while the solid part B is added, thereby forming a homogeneous whipped mixture and lowering the density of the whipped mixture by addition of air introduced by the whipping until the weight of the whipped mixture is approximately 3.8 to 4.5 pounds per gallon;  
       (D) placing the whipped mixture into a mold carrying a gas tube defining at least one hole and having a gas connection fitting; and  
       (E) curing and demolding the active log.